Last year (2019), I was amazed by how well the spring season had begun. Huge amounts of rain and snow helped replenish a lot of what was lost the year before. There was so much precipitation in fact, that reservoirs were overflowing and some places in the high sierra were able to keep the ski slopes open until the middle of July! Thanks to all of this wonderful weather in the winter to early spring, flower blooms and insect densities were at some of the highest I had seen them in a very long time. From the UC Davis Arboretum to the foothills of the Sierra Nevada, spring was in full force and I was lucky enough to witness all of these amazing changes to the region.

A Great Start to an Amazing Year

Spring of 2019 had begun to show itself around mid to late March, with many flowers beginning to bloom and insect activity increasing to a noticeable amount. Areas around the county were in full bloom by the end of the month and the UCD Arboretum was not far behind. Fields of mustard flowers and wildflowers along roadsides were growing in numbers and growing in intensity with each passing day. Cooler temperatures and occasional bouts of rain kept these blooms around for much longer than anticipated.

As more blooms started to appear, so did the insects. To my surprise, the painted lady butterflies migrating from southern to northern California made it to the area in time to catch the strongest part of the spring bloom. In the Arboretum, many different species of plants were in bloom and these flowers were buzzing with activity. Carpenter bees, honey bees, small native bees, painted lady butterflies, and hover flies were just some of the insects I saw visiting flowers around the Arboretum and in neighboring areas.

Around early to mid April is when everything was in full bloom. I did a small insect survey near the Foresthill area, east of Auburn, and found that insects were out in full force. The area was full of blooming redbud trees and ceanothus bushes, both of which had insects visiting them frequently. I couldn’t even count how many Sara orange-tip butterflies and Mendocino saturnia moths I saw flying by me, it was an amazing sight. Saturnia mendocino is by far one of the most difficult moths I have ever attempted to catch, at least in mid flight. Another notable lep that was fairly common in this area was the silvery blue butterfly (Glaucopsyche lygdamus). Its bright and reflective blue color was really great to see in the warm sun. A week or so after this short weekend trip, I decided to check out Stebbins Cold Canyon and see how it was progressing.

Cold Canyon was starting to bloom and the insect activity seemed like it had a good jump on the spring flowers. Mules ear flowers (Wyethia sp.), ceanothus bushes, lupines, and California pipevines (Aristolochia californica) were just some of the plants in bloom up and down the canyon. Sara orange-tips (Anthocharis sara) and cabbage whites were the more abundant butterflies in the canyon, while mourning cloaks (Nymphalis antiopa) would only seldom make an appearance in certain areas. In addition to all the amazing blooms and awesome insect species that were present in the canyon, the creek that is usually dry, was very full and flowing very loudly. I tend to use Stebbins Cold Canyon as an indicator of how good, or bad, spring will be in the area and in other areas nearby. If this area is doing very well in the early to mid spring, then more likely than not the areas at higher elevations will be just as good, if not better as the season progresses.

  • Ceanothus bloom
  • These lupines were very abundant!
  • California pipevine
  • Sawfly (Tenthredinidae)
  • Wyethia sp.
  • Longhorned bee (male)

As the season progressed and spring began to transition to summer, flower blooms and insect populations gradually increased until they peaked around late June to early July. I was unable to visit the Saghen Creek area last year (2019), but I will try my best to make it up there during the summer in 2020. I am hopeful for what the spring season will have in store during 2020, but the determining factors will be precipitation (rain/snow) and lower daily temperatures. If that happens in the region, then I know the spring will last for a good while, but if not, then the spring season will be short lived.

  • Clusters of longhorned bees on sunflowers were in abundance.

Due to 2019 ending in a busy way for me, I was unable to get this post out sooner. Fortunately, I will be able to look back at this for comparisons to how the spring shapes up this year (2020).